Purchase this article with an account.
Julio A Urrets-Zavalia, Leandro Correa, Evangelina Esposito, M. Eugenia Gonzalez-Castellanos, Dana Martinez, fernanda Suarez, Horacio M Serra; Refractive errors in a rural population of Argentine Patagonia. Invest. Ophthalmol. Vis. Sci. 2015;56(7 ):2208.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
Information of refractive errors prevalence in rural populations in Argentina is lacking. The purpose of our study was to assess the prevalence of refractive errors in an adult rural population living in an area of the Argentine Patagonia.
An observational, descriptive and retrospective study was performed to assess the frequency of myopia, hyperopia, astigmatism and anisometropia in 144 consecutive adult patients, 76 men and 68 women, of mapuche etnia from a rural region of the Argentine Patagonia. All patients received a comprehensive eye examination, including visual acuity with Snellen chart, and refraction was obtained under cycloplegia. Refractive errors were evaluated in spherical equivalent (SE). Myopia and hyperopia were defined as spherical equivalent (SE) ± 0.50. All patients with SE less than ± 0.50D were considered as emmetropic. Astigmatism was defined as a cylinder equal or greater than 0.50D. Anisometropia was defined as the difference in spherical equivalent of > 1.00D between the two eyes. Each refractive error was separated into three different groups: low (less than 1d), moderate (1-3D) and severe (> 3d) astigmatism; low (<+2D), moderate (+2.25 to +5D) and severe (more than+5D) hyperopia; low (less than -3D), moderate (-3 to -6D) and severe (more than -6D) myopia . As the Spearman correlation coefficient for the SE and the cylinder between the right and left eye was high (r = 0.86, P <0.0001), only data from the right eye were used for analysis. Anisometropia was analyzed with SE data of both eyes. Variables with a p<0.05 were considered as significant.
Median age was 55.5 years (r= 20-84 years). The prevalence for emmetropia was 34% (95% CI = -0.38, 0.38); myopia 18% (95% CI = -21.25, -0.50), being more prevalent in women (p<0.001), much more frequently involved in near work tasks; hyperopia was 46.5% (95% CI = 0.5; 4.38); and astigmatism 63.2% (95% CI = 0.5; 5.5). Low (30.6%) and moderate (26.4%) astigmatism were more prevalent. 86,6% of hyperopic patients had low hyperopia, 11,9% moderate and the 1,5% had severe hyperopia. Among myopic patients 73.1% had low, 11.5% moderate and 15.4% severe myopia. Anisometropia prevalence was 14.6% (95% CI = 1; 20.5).
Astigmatism, in particular low and moderate, was found to be highly prevalent among this rural population. Environmental factors and type of activity might contribute to astigmatism and myopia, respectively.
This PDF is available to Subscribers Only